scholarly journals Study of the influence of chemical anti-icing materials on frost heaving of the roadbed soils

2020 ◽  
Vol 220 ◽  
pp. 01064
Author(s):  
A. Y. Velsovskij ◽  
V. A. Shorin ◽  
T.R. Akhmetov

This work examines the influence of chemical anti-icing materials on the frost resistance of the road pavement. Methods and technologies for introducing salt additives into the soil are considered. The preparation of soil with salt additives for testing for frost heaving is described. The kinetics of frost heaving processes of the reference soil sample and soil treated with salt additives was investigated. The influence of type and concentration of the salt additive on the degree of frost heaving of soils was investigated. The negative impact of chemical anti-icing additives on the indicators of frost heaving of soils, especially with uneven salinity, was registered.

2020 ◽  
Vol 161 ◽  
pp. 01038 ◽  
Author(s):  
G L Kagan ◽  
V. A. Shorin ◽  
A. Y. Velsovskij

The paper discusses the negative impact of heaving soil during freezing of a road structure, including heaving formation. The provisions of normative methodology for testing the road structure for frost resistance are considered. The results of indirect and laboratory tests for determining the soil group by the degree of heaving are analyzed. The validity of influence of natural factors on frost heaving is considered. Proposals for improving the normative methodology are put forward.


2019 ◽  
Vol 262 ◽  
pp. 05019
Author(s):  
Magdalena Złotowska ◽  
Roman Nagórski ◽  
Piotr Radziszewski ◽  
Michał Sarnowski ◽  
Paweł Tutka

Asphalt road pavements are subject to damage under the influence of loads from the traffic of vehicles and of the environmental factors. One of the ways to strengthen damaged flexible pavements is to apply a cement concrete overlay with continuous reinforcement. The purpose of this paper is to analyze the road structure with concrete overlay with continuous reinforcement HFRP composite bars, which is laid on the existing cracked asphalt layers of a typical flexible road of KR3 traffic category. In HFRP bars some of the basalt fibers have been replaced with carbon fibers with the addition of resin binders. This do the possibility of making concrete slabs with increased resistance for environmental aggression, with good mechanical properties, which is especially important in the case of road constructions. An analysis of fatigue life of the strengthened asphalt pavement with a concrete slab with continuous reinforcement of HFRP bars was carried out, implementing the mechanistic model of the pavement structure. The stress analysis in the structure under the action of static loading was determined by the Finite Element Method using the Abaqus/Standard program. The maximum value of stress caused by temperature gradient in the concrete slab was calculated from the Westergaard’s formula for infinite slab. It has been shown that strengthening the analyzed road pavement with a continuous reinforcement is a technology that ensures an increase in fatigue life and reinforcement with HFRP bars further increases durability due to the negative impact of environmental factors.


Author(s):  
С. В. Гошовец

Состояние проблемы. Считается, что уменьшение толщины слоя в пределах допуска не оказывает существенного влияния на надежность и долговечность дорожной одежды. Так как конструкция дорожной одежды, как правило, состоит из нескольких слоев, можно предположить, что занижение толщины слоев в пределах допуска может оказать негативное влияние на прочность конструкции в целом. Применительно к отечественным нормам проектирования и строительства данное предположение остается не изученным. Результаты. Проведен анализ показателей, характеризующих толщину слоя, и практик назначения строительных допусков. Проанализированы исследования влияния допуска на надежность дорожной одежды и рекомендации по корректировке толщины слоев конструкции под влиянием допусков. Выполнены моделирование и расчет конструкций с учетом допусков. Выводы. Полученные результаты подтвердили предположение о том, что уменьшение толщины слоев дорожной одежды в пределах допусков негативно влияет на все критерии прочности. Предложено решение по устранению несогласованности между строительными допусками и нормами проектирования. Statement of the problem. Reducing the layer thickness within the tolerance is considered not to have a significant effect on the reliability and durability of the road surface structure. Since the construction of roadways usually consists of several layers, the assumption that understating the thickness of the layers within the tolerance can have a negative impact on the overall strength of the structure is not unreasonable. In relation to the domestic standards for the design and construction of this assumption has not yet been studied. Results. The analysis of indicators characterizing the layer thickness and practices for the purpose of construction tolerances, analysis of recommendations in the design standards for correcting the thickness of the layers of the structure due to the influence of tolerances, studies of the influence of tolerance on the reliability of road pavement, modeling and calculation of structures with allowances, suggestions are provided. Conclusions. The results confirmed the assumption that reducing the thickness of road surface layers within the tolerance limits negatively affects all the strength criteria. We have proposed a solution in order to eliminate inconsistencies between construction tolerances and design standards.


2021 ◽  
Vol 2021 ◽  
pp. 102-116
Author(s):  
Vasyl Nahaichuk ◽  

Abstract Introduction.Road pavement is one of the most material-intensive and expensive elements of the road. The quality and durability of the road as a whole depend on the type of road construction material and the method of its application. Considering the significant needs of the road industry in construction materials, there is a need to find effective materials, the use of which allows building the road pavement that can resist the loadings of modern vehicles during the standard service life of pavement. In order to minimize the cost of construction and the negative impact on the environment, it is advisable to use local stone materials, the use of which allows obtaining the efficient road structures on their basis, requires minimal transportation costs and contributes to environmental protection.Problem statement. On the territory of Ukraine there are many deposits of stone materials and products of their associated processing in the form of crushing screenings [1–5]. These materials can be used as the stone materials for pavement layers arrangement without reinforcing binders, also for improving of their properties by strengthening with various types of binders.For strengthening and improving the properties of stone materials can be used the following:–inorganic binders, which include cement, lime and slag alkaline binder;organic binders, which include bitumen, bituminous emulsions and foamed bitumen–complex binders in the form of combination of cement with bitumen, as well as cement with bitumen emulsion or foamed bitumen.Considering the growth of transport loadings on road structures, it is necessary to provide the use of reliable and durable structures, for the construction of which it can be used available domestic raw materials. Organic binders, which include bitumen imported to Ukraine, are quite expensive and their cost is constantly rising. One of the perspective ways for solving this problem is the use of slag alkaline binders and concretes on their basis in the road construction, using local stone materials of different genesis as aggregates.Purpose. The purpose is to study the possibility of obtaining effective slag alkaline concrete with use as a mineral aggregate the stone materials of different mineralogical composition and strength, suitable for non-rigid pavement layers arrangement, capable to operate under repeated short-term loadings.Materials and methods. The erupted and sedimentary rocks that most widespread in Ukraine were used for study, namely: organic-hemogenic limestones, quartzite-like sandstones and granite materials. Blast furnace granulated slag and soda alkali flux were used as binder components. The mechanical properties and physical and chemical processes that occurred during the slag alkaline hardening were studied, and the technological parameters and the features of preparation of such concretes were studied. The state of the contact zone between the slag alkaline stone binder and various aggregates was determined by a set of methods allowed studding the physical and mechanical characteristics of the contact zone (micro hardness) and determining the distribution of the concentration of basic chemical elements in the contact zone, the composition of new formations and its microstructure.Results. The possibility of obtaining of effective slag alkaline concrete on aggregates of different mineralogical composition and strength that are suitable for non-rigid pavement layers arrangement that are capable for operating under repeated cyclic loadings, was theoretically determined and experimentally confirmed.Keywords: slag alkaline concrete, limestone, granite, sandstone, blast furnace milled granulated


Author(s):  
Elizaveta Derevenets ◽  
Elizaveta Derevenets

Gelendzhik is the resort town, there aren't a lot of industrial enterprises here. The main pollutant is transport. The work purpose is the assessment of a condition of the artificial landings of a pine located along the Federal highway "Don" and landings, which is nearly the sea coast. Researches were conducted to a standard technique of the General vital state (A. S. Bogolyubov). The assessment of a condition of pines was carried out during 6 years: from 2010 to 2015. For carrying out research we used 6 experimental grounds on the Markotkhsky spine and 2 control grounds within the town. We investigated 24 trees on each platform, middle age of the trees were 30 - 40 years. Results. 1. The condition of trees in the pine forests located in immediate proximity with the Federal highway "Don" (No. 1, 2, 3) is unsatisfactory. As even weak influences of the majority of atmospheric gaseous pollutants (sulphurous gas, nitrogen oxides, etc.) give effect of a necrosis and hloroz of pine needles, the condition of pines is connected with technogenic pollution. So near the Federal highway "Don" the air environment is strongly polluted by exhaust gases. Information of 2012 confirm that negative influence of the route on Markotkh's vegetation decreases at reduction of load of the route. 2. On the sites located above on a slope (No. 4,5,6) thanks to remoteness and the wind mode intensity of influence of pollutants is lower and a condition of pines the quite satisfactory. 3. Trees on the sites located near the sea (No. 7,8) are in a good shape. Small deterioration of a state is noted in very droughty years. Conclusion. Results of six years' research show that the condition of the plantings which are in close proximity with the road worsens. It is explained by increase in intensity of the movement on the road, especially during a resort season. Gelendzhik is the city with a good ecological shape, but the damage to environment is already caused. If not to take measures, we can lose a unique part of the nature in the future, recreate it will be impossible. Measures of reduction of negative impact of exhaust gases were offered. Results of researches are transferred to ecological department of the City administration of Gelendzhik.


2018 ◽  
pp. 128-145
Author(s):  
Volodynyr Mozghovyi ◽  
◽  
Viktor Gaidaichuk ◽  
Yurii Zaiets ◽  
Liudmyla Shevchuk ◽  
...  

Author(s):  
Elizaveta Derevenets ◽  
Elizaveta Derevenets

Gelendzhik is the resort town, there aren't a lot of industrial enterprises here. The main pollutant is transport. The work purpose is the assessment of a condition of the artificial landings of a pine located along the Federal highway "Don" and landings, which is nearly the sea coast. Researches were conducted to a standard technique of the General vital state (A. S. Bogolyubov). The assessment of a condition of pines was carried out during 6 years: from 2010 to 2015. For carrying out research we used 6 experimental grounds on the Markotkhsky spine and 2 control grounds within the town. We investigated 24 trees on each platform, middle age of the trees were 30 - 40 years. Results. 1. The condition of trees in the pine forests located in immediate proximity with the Federal highway "Don" (No. 1, 2, 3) is unsatisfactory. As even weak influences of the majority of atmospheric gaseous pollutants (sulphurous gas, nitrogen oxides, etc.) give effect of a necrosis and hloroz of pine needles, the condition of pines is connected with technogenic pollution. So near the Federal highway "Don" the air environment is strongly polluted by exhaust gases. Information of 2012 confirm that negative influence of the route on Markotkh's vegetation decreases at reduction of load of the route. 2. On the sites located above on a slope (No. 4,5,6) thanks to remoteness and the wind mode intensity of influence of pollutants is lower and a condition of pines the quite satisfactory. 3. Trees on the sites located near the sea (No. 7,8) are in a good shape. Small deterioration of a state is noted in very droughty years. Conclusion. Results of six years' research show that the condition of the plantings which are in close proximity with the road worsens. It is explained by increase in intensity of the movement on the road, especially during a resort season. Gelendzhik is the city with a good ecological shape, but the damage to environment is already caused. If not to take measures, we can lose a unique part of the nature in the future, recreate it will be impossible. Measures of reduction of negative impact of exhaust gases were offered. Results of researches are transferred to ecological department of the City administration of Gelendzhik.


2019 ◽  
Vol 13 (3) ◽  
pp. 235-240
Author(s):  
Iryna Solonenko

The development of road network infrastructure is an important component of the economic development of the European Union. Updating of the road network contributes to the integration of the economies of countries into a coherent whole. The road network provides the free movement of citizens, the movement of goods and the effective implementation of various services. The increase in the length of the road network leads to an increase in the financial and material costs necessary to ensure its maintenance and repair. One of the ways to reduce costs is by strengthening the physic-mechanical and operational characteristics of the pavement due to the widespread use of cement concrete. The quality of the pavement of cement concrete depends largely on the rational selection of its composition. This allows a significant increase in the durability of road pavement. The purpose of the research was: the development of recommendations for the rational selection of the composition of the road pavement material of cement concrete, aimed at upgrading longevity, and taking into account its frost resistance grade. According to the goal, the following tasks were developed: the analyses of the climatic zones in which the road network of the European Union is located; the development of a research plan, a selection of the response function and influence factors; the study of physico-mechanical and operational characteristics of the researched material of road pavement; on the basis of the obtained data, the calculation of the complex of experimental-statistical models, which describe the physico-mechanical and operational characteristics of the road pavement material; on the basis of experimental statistical models, a method was proposed for selecting the rational compositions of the cement concrete pavement road material depending on the conditions of its application. The results presented in the article can be used in engineering and scientific practice for the selection of road pavement from cement concrete for highways.


2021 ◽  
Vol 13 (11) ◽  
pp. 5899
Author(s):  
Yeonsoo Jun ◽  
Juneyoung Park ◽  
Chunho Yeom

This paper evaluates experimental variables for virtual road safety audits (VRSAs) through practical experiments to promote sustainable road safety. VRSAs perform road safety audits using driving simulators (DSs), and all objects in the road environment cannot be experimental variables because of realistic constraints. Therefore, the study evaluates the likelihood of recommendation of VRSA experimental variables by comparing DSs experiments and field reviews to secure sustainable road safety conditions. The net promoter score results evaluated “Tunnel”, “Bridge”, “Underpass”, “Footbridge”, “Traffic island”, “Sign”, “Lane”, “Road marking”, “Traffic light”, “Median barrier”, “Road furniture”, and “Traffic condition” as recommended variables. On the contrary, the “Road pavement”, “Drainage”, “Lighting”, “Vehicle”, “Pedestrian”, “Bicycle”, “Accident”, and “Hazard event” variables were not recommended. The study can be used for decision making in VRSA scenario development as an initial effort to evaluate its experimental variables.


2021 ◽  
Vol 1125 (1) ◽  
pp. 012019
Author(s):  
Yosef Cahyo Setianto Poernomo ◽  
Sigit Winarto ◽  
Zendy Bima Mahardana ◽  
Dwifi Aprillia Karisma ◽  
Rekso Ajiono

Sign in / Sign up

Export Citation Format

Share Document